To separate pyrophosphate(H2P2O72-) and tripolyphosphate (H3P3O102-) by ionexchange, an acidic eluent where they have a low ionic value is employed.
Sample : 150mg/L each, 100µL
1. H2P2O72-
2. H3P3O102-
Column : Shodex IC NI-424 (4.6mmID*100mm) Eluent : 8mM H2SO4 + 0.04mM EDTA·2Na aq. Flow rate : 1.0mL/min Detector : Shodex RI Column temp. : 40°C